[A family with dominant-phenotype Beta-thalassemia].

We report a 43-year-old Japanese woman with microcytic and hypochromic anemia, who had been erroneously diagnosed as having iron deficiency anemia 20 years previously at the time of her first labor, and treated with iron and blood transfusion. At the present visit to our clinic, she was found to have an increased HbA2 level and prolonged glycerol lysis time. Genetic analysis of the beta-globin gene revealed deletion of 3 bases at codons 127/128 (CAG/GCT-->CCT). A genetic study of the patient's family showed that two of her four children possessed the same mutation. The patient had mild anemia, her first son had very mild anemia, and her second daughter had moderate anemia with hemolysis. These affected family members were diagnosed as having dominant-phenotype beta-thalassemia.